Some of the early solar watches of the 1970s had innovative and unique designs to accommodate the array of photovoltaic solar cells needed to power them. In the 1990s, Citizen started to sell light-powered watches under the Eco-Drive series name. Since their introduction, solar devices have greatly improved their efficiency and thereby their capacity. Watchmakers have developed their technology such that solar-powered watches are now a major part of their range of watches. Some.. Read More